The early-type semidetached binary system V716 Centaurus

Abstract

New high‐resolution spectra of V716 Cen revealed for the first time lines of the secondary component and its radial velocities. The simultaneous solution of the new radial velocity curves and the Hipparcos light curve yield the reliable absolute dimensions of this semidetached system. The masses for the primary and secondary are M1= 5.68 ± 0.07 M⊙ and M2= 2.39 ± 0.05 M⊙, respectively, and the radii are R1= 4.08 ± 0.07 R⊙ and R2= 3.36 ± 0.02 R⊙. We derive also effective temperatures of Teff1= 15 500 ± 50 K and Teff2= 9000 ± 80 K, and equatorial rotational velocities of vrot sin i= 137 ± 2 km s−1 and vrot sin i= 116 ± 7 km s−1. These rotational velocities imply that the components rotate synchronously. The distance to the system is d= 339 ± 8 pc, in good agreement with the less accurate Hipparcos distance (337 ± 72 pc). The primary is underluminous and the secondary overluminous compared to normal main‐sequence stars of the same mass. This implies that the secondary component of the semidetached system is in slow mass transferring stage after mass ratio reversal, although the Hα‐line profiles do not show clear evidence for this.

The Multiple Star η Muscae

“…The arrangement of this paper follows along similar lines. A previous related study was that of Bakış et al (2007), whose radial velocity (RV) amplitudes we are in good agreement with. There are differences in analysis methods between Bakış et al and the present contribution, however, and also our inferences are significantly different, particularly after the identification of η Mus D, as well as our ‘occultation’ assessment of the primary eclipse.…”

The spectroscopic orbits of three double-lined eclipsing binaries: I. BG Ind, IM Mon, RS Sgr

“…In this paper, we have observed and studied three Algol-type eclipsing binaries (BG Ind, IM Mon and RS Sgr) of which apparently have not yet studied with a sufficient accuracy and thus their physical parameters in the literature are absent nor accurate to understand their orbits and physical natures. Being one of a series (Bakış et al, 2007;Bakış et al, 2008a;Bakış et al, 2008b) of publications, here now we announce the optical spectra and spectroscopic elements of BG Ind, IM Mon and RS Sgr.…”

Interstellar magnetic cannon targeting the Galactic halo

“…With these parameters, the star system past orbit was at ∼4.7 pc from the bubble centre around 2.8 Myr ago. The orbit using the radial velocity derived by Bakış et al (2008;B2008) does not converge inside the bubble. Only the radial velocity −10.3 km s −1 has been used to calculate the trajectory in B2008.…”

“…V716 Cen astrometric parameters are taken from Gaia Collaboration (2016). Radial velocities (v rad ) are taken from (a,b) Kharchenko et al (2007) and (c) Bakış et al (2008). One of the runaway star trajectories studied by Hoogerwerf et al (2001), in addition to ζ Oph, might have been in the vicinity of the USco association in the past.…”

“…Hoogerwerf et al (2001) used a radial velocity of +66 ± 10 km s −1 , which is the same as provided by the SIMBAD search database. Jilinski et al (2010) in their dynamical study of runaway stars produced through the BSS process in the Sco-Cen, used the radial velocity −10.3 ± 6.9 km s −1 derived by Bakış et al (2008) by averaging systemic velocities obtained from measured separated He I and Mg II lines. Figure 14 shows the closest trajectory for a radial velocity of ∼57 km s −1 (H2001) and a bubble distance of ∼138 pc.…”